This invention relates in general to electronic timing devices and, in particular, to electronic parking meters.
Both mechanical and electronic parking meters are well known in the prior art and are typically of the type which are responsive to the insertion of a coin to begin timing an interval for a vehicle parked in an appropriate space associated with the parking meter. The timing interval is typically determined by the number and value of the coins which are inserted into the parking meter. The parking meter can be associated with a single parking space or a single parking meter may be used for an entire lot of multiple spaces.
It is a feature of the present invention to provide an electronic parking meter which is more dependable, has a greater variety of features, and is more economical to manufacture than prior art parking meters. It is an advantage of the present invention that the novel electronic parking meter can identify and reject non-metallic coins.
U.S. Pat. No. 4,792,032 discloses a parking meter which has a coin carriage that moves a deposited coin on a coin track having cam surfaces. When the coin is moved over the cam surface a switch is activated and provides a signal to the electronic circuitry in the parking meter. A drawback of such a structure is that non-metallic coin-shaped elements can be used to activate the parking meter. U.S. Pat. No. 4,792,032 is hereby incorporated by reference in regards to the structure depicted in FIG. 2A of this patent. U.S. Pat. No. 3,757,916 depicts in FIG. 7 thereof another version of a coin winding mechanism.